Presented in part as Abstract 1588 at the 39th annual meeting of the American Society of Clinical Oncology, Chicago, Illinois, May 31–June 3, 2003.

Abstract

BACKGROUND

The objective of this study was to assess the biologic activity of rosiglitazone, a peroxisome proliferator-activated receptor γ agonist that has been approved to treat type 2 diabetes, in men with recurrent prostate carcinoma using change in prostate specific antigen (PSA) doubling time (PSADT) as the primary outcome variable.

METHODS

Men with histologically confirmed prostate carcinoma, no recent hormone therapy, a rising serum PSA level after radical prostatectomy and/or radiation therapy, and no radiographic evidence of metastases were assigned randomly to receive either oral rosiglitazone (4 mg twice daily) or placebo. The treatment was continued until the men developed disease progression or adverse effects. A positive outcome was defined as a posttreatment PSADT > 150% the baseline PSADT and no new metastases.

RESULTS

One hundred six men were enrolled. The median treatment duration was 315 days for men in the placebo group and 338 days for men in the rosiglitazone group (P = 0.28). Forty percent of men in the in the placebo group and 38% of men in the rosiglitazone group had a posttreatment PSADT > 150% of the baseline PSADT and no new metastases (P = 1.00). In exploratory analyses, the rate of a positive outcome remained higher than expected in the placebo group, even when a positive outcome was redefined using more stringent criteria. The time to disease progression was similar between the groups.